Trample
Whenever another artifact enters the battlefield, put a +1/+1 counter on Arcbound Crusher.
Modular 1 (This enters the battlefield with a +1/+1 counter on it. When it's put into a graveyard, you may put its +1/+1 counters on target artifact creature.)

Whenever Arcbound Slith deals combat damage to a player, put a +1/+1 counter on it.
Modular 1 (This enters the battlefield with a +1/+1 counter on it. When it's put into a graveyard, you may put its +1/+1 counters on target artifact creature.)

As Arsenal Thresher enters the battlefield, you may reveal any number of other artifact cards from your hand. Arsenal Thresher enters the battlefield with a +1/+1 counter on it for each card revealed this way.

Other red creatures you control get +1/+1.
Other white creatures you control get +1/+1.
Whenever you cast a red spell, Balefire Liege deals 3 damage to target player.
Whenever you cast a white spell, you gain 3 life.